Reactor Physics and Dynamic Group (RPD) KIT Multi-Physics Developments for Reactor Analysis Víctor Hugo Sánchez Espinoza (victor.sanchez@kit.edu) Institute for Neutron Physics and Reactor Technology (INR) KIT The Research University in the Helmholtz Association www.kit.edu
Content Motivation KIT strategy for R&D Coupling of transport solvers with subchannel codes How to validate pin-by-pin deterministic solutions? Coupling of Monte Carlo with subchannel codes Validation of high fidelity codes Summary and Outlook 2 1 st KIT-SJTU Student Workshop
Motivation- Development of Reactor Technology Gen- II LWR: PWR Konvoi BWR Type-72 Gen- III LWR: AP-1000 ABWR Gen-IV: SMR SMART MTR Research Reactors LFR (ADS) SFR 3 1 st KIT-SJTU Student Workshop
Motivation- Increasing Cheap and Powerful Computer Clusters PRACE: Partnership for Advanced Computing in Europe Barcelona Supercomputing Center (Spain), CINECA Consorzio Interuniversitario (Italy) EPCC at the University of Edinburgh (UK), GCS Gauss Centre for Supercomputing (Germany) Maison de la Simulation (France) HPC computer Centers in state Baden Württemberg KIT HPC Infrastructure bwunicluster (bwhpc concept, Tier 3, BW Unis) 872 SMP-parallel nodes, 86 TB main memory, 444 TFLOPS peak power and Job with small number of processors bwforcluster (4 Research HPC Clusters in BW) bwforcluster MLS/WISO: Economics /social sciences (Mannheim/Heidelberg) bwforcluster JUSTUS: Chemistry (Ulm) bwforcluster NEMO: Neuro sciences. Microsystems, elementary particle physics (Freiburg) bwforcluster BinAC: Bio informatics and astro physics Research High Performance Computer ForHLR I and II (Trier 2) Phase I: applications with many thousands processors Phase II: applications with many hundred thousands processors ( Intel Xeon-processors, 1.2 PFLOPS power, 24 000 cores KIT/INR: McSAFE Project: 100 000 CPUs KIT SCC ForHLR I KIT SCC ForHLR II 4 1 st KIT-SJTU Student Workshop
Motivation: Challenges for core Physics CPU Time FA-Cluster Reactor core Methods: Neutronic: Deterministic / MC TH: Subchannel / CFD Long term Fuel Assembly (FA) pin Pin cluster Methods: Neutronic: Diffusion Thermal Hydraulic: 1D TH now # of Degree of Freedom 5 1 st KIT-SJTU Student Workshop
KIT/INR Strategy for the Development of Safety Analysis Codes Selection of Key Safety Topics combining innovative Research with E&T Reflecting needs of German situation Following international trends Integration of RPD activities in national / international activities and programs EU projects National programs and projects of BMBF, BMWi, etc. Strategic Partnership with Key Players Industry partnership based on innovative research Regulators and TSO Research centers and universities (national, international) Combination of In-house code development and use of external numerical tools Make use of HPC and development of algorithms 6 1 st KIT-SJTU Student Workshop
KIT/INR Research Topics (Examples) Selected research directions: Code development /extensions for improved core analysis including neutronics, thermal hydraulics, thermo-mechanics, chemo-physical phenomena important for DBA and SEVERE ACCIDENTS Extend and improve prediction capability by multi-physics and multi-scale approaches for DBA analysis Development and validation of SEVERE ACCIDENT codes SAM-optimization for BWR and PWR Uncertainty quantification of numerical safety analysis tools Verification, validation and application to different reactor types 7 1 st KIT-SJTU Student Workshop
KIT Multi-Scale Thermal Hydraulic Coupling Goal: Improve the description of TH phenomena inside the RPV, Core and Loops System TH Code: TRACE, RELAP5, ATHLET: whole NPP simulation at macro scale 1D or 3D coarse mesh TH Empirical correlations Fast running Subchannel TH Code: SUBCAHNFLOW, CTF: simulation of the reactor core TH at component scale. Detailed description of cross flow physics between Sub-channels or fuel assemblies CFD Codes: 3D simulation at different details (mm to m) Less empirical models Almost exact geometry Porous media approach to reduce CPU and make it practicable LOOPS: TRACE, RELAP5 Core N and TH: TRACE/PARCS SCF/PARCS Blue: CFD: DWC, LPLN, UPLN 8 1 st KIT-SJTU Student Workshop See presentation of PhD K. Zhang RPV except Core: CFD Core: TRACE/PARCS SCF/PARCS
Coupling of Neutronics-Thermal Hydraulics and Thermo- Mechanics 9 1 st KIT-SJTU Student Workshop
MPI-based Coupling of PARCS/SCF/TRANSURANUS Goals: Improve description of core behaviour under irradiated conditions during life time Coupling approach: Tc master slave slave Dc Tf (avg) Trod (rad) PARCS SCF TU 10 1 st KIT-SJTU Student Workshop Tc CC HTC Pres Lin Pow MPI-based Approach Transferred variables Tc Coolant temperature Dc Coolant Density Tf Fuel Temperature Trod Rod radial temperature Lin Pow Linear Power Pres Pressure CC HTC Clad Coolant heat transfer coefficient See presentation of PhD J. Basualdo
Coupling of Transport Solvers with subchannel codes (DYNSUB5) 11 1 st KIT-SJTU Student Workshop
Motivation: From industry standard to advanced N/TH core simulations Best-estimate codes: based on nodal diffusion and coarse TH (1D, 3D) TRACE/PARCS, ATHLET/DYN3D, CATHARE/CRONOS2, etc. Industrial standard DYN3D DYN3D DYN3D Nodal core simulations research COBAYA3k-CTF (PWR) Next step: Advanced Neutronic /thermal hydraulic coupling: Replace nodal diffusion by transport solvers (SP3) and system TH by SCF: DYNSUB5 12 1 st KIT-SJTU Student Workshop
Pin-by-pin DYNSUB5 Transient Analysis of the PWR MOX REA DYNSUB5 Analysis of PWR REA Simulation: Transient HZP (3.565kW), TC=560 K Ejected rod: E5 within 0.1 s Time step: 5 ms Highest power in fresh UOX Validation with experimental data needed Evolution of thermal power during HZP rod ejection accident (REA) HZP rod ejection accident (REA): axially cumulated power density distribution [W/cm³] at 0.22s Run statistics: Platform: Xeon E5620 4 CPUs Run time: 14 days and 7 h 13 1 st KIT-SJTU Student Workshop PhD: M. Däubler Code-to-code comparison: Nodal and SP3 Solutions
How to Validate the Pin-by-Pin Deterministic Solutions? 14 1 st KIT-SJTU Student Workshop
Motivation: Validation of Numerical codes used in Industry and Licensing Diffusion + Pin Power Re-construction (PPR) Experimental Data PWR FA DYN3D-PPR: NURISP PWR Boron Dilution Benchmark SP3 Transport /Subchannel DYNSUB5: 3D Pin Power Density [W/cm³] Advanced Deterministic Methods 15 1 st KIT-SJTU Student Workshop OR Monte Carlo with TH feedback provide reference solutions PWR 3x3 FA Cluster PWR ¼ Core ( 56 FAs) MCNP5/SUBCHANFLOW: High Fidelity Simulations at pin level
Internal coupling of MCNP5/SUBCHANLOW Internal coupling of SERPENT2/SUBCHANFLOW 16 1 st KIT-SJTU Student Workshop
Internal Serpent2/SUBCHANFLOW coupling Data exchange via memory SUBCHANFLOW ASCII file I/O PhD: M. Däubler M. Daeubler, B. L. Sjenitzer, A. Ivanov, V. Sanchez, R. Stieglitz und R. Macian-Juan, High-fidelity coupled Monte Carlo neutron transport and thermal-hydraulic simulations using Serpent 2/SUBCHANFLOW, Annals of Nuclear Energy, pp. 352-375, 2015. 17 1 st KIT-SJTU Student Workshop
SERPENT2/SCF Coupling: Main Features Feedback treatment: same as original SERPENT Fuel temperature: Predicted by SUBCHANFLOW (Cartesian mesh-based) TMS is not applicable to thermal bound scattering (S(α,β) thermal scattering data) and unresolved resonances probability table sampling New approach to treat thermal bound scattering: Automatically fall back of SERPENT to stochastic mixing where TMS is not applicable Moderator density: Predicted by SUBCHANFLOW and passed to MC tracking routine via multi-physics interface Methods to pass density to MC tracking routine: Cartesian mesh-based, point-wise and user-defined functional distribution Internal coupling Automatic generation of geometry tables for TH solver (SCF) assuring appropriate mapping between N and TH Relaxation scheme based on Stochastic Implicit Euler method (J. Dufek) Convergence criteria based on I²-norm (Euclidean Norm) for feedbacks (Doppler or moderator density) 18 1 st KIT-SJTU Student Workshop
Serpent2/SCF: High fidelity Simulation of the HFP PWR MOX/UOX Core (1/2) Channel and sub-channel TH model of OECD NEA and U.S. NRC PWR MOX/UO2 core transient benchmark Core Thermal hydraulics: 193 subchannels 20 axial levels Core model at subchannel level: Neutronics nodes: 55777 pins and guide tubes Thermal hydraulics: 35 axial levels, 62532 sub channels Fluid: 2.2 M cells, Solid: 23.4 M Solution approach: Pin-by-pin solution Per iteration step: 4 E6 neutrons per cycle 650/2500 inactive/active cycles Convergence criteria: T-Doppler and M-density= < 0.5 % 19 1 st KIT-SJTU Student Workshop
Serpent2/SCF: High fidelity Simulation of the HFP PWR MOX/UOX Core (2/2) 5M neutrons per cycle, 2000 active cycles per iteration SSS2/SCF Subchannel level: 5.8 CPU years at KIT IC2 HPC Cluster: Intel Xeon E5-2670, InfiniBand KIT IC2 HPC: 16 to 2048 cores (1 to 128 nodes) TH: subchannel level 5.8 CPU-Y= 5.8 x 365 d / 2048 = 1.03 days PhD: M. Däubler SSS2/SCF: 3D Power Distribution KIT IC2: one node of 16 cores: 64 GB memory 20 1 st KIT-SJTU Student Workshop
How to make sure that MC/TH solutions are accurate? 21 1 st KIT-SJTU Student Workshop
Serpent2/SCF Validation Code-to-code comparison OECD NEA/ US NRC PWR MOX/UOX REA Core Transient Benchmark (ss conditions) Code-to-data comparison Experiments like VENUS 1 and 2 critical experiments MIT BEAVRS benchmark HZP physics test HP measurements at 18 days (693 MWth) after BOL SPERT III E steady state conditions 22 1 st KIT-SJTU Student Workshop
PWR BEAVRS Cycle 1 HZP physics tests (25 MWth) HP measurements at 18 calendar days (692.7 MWth) after BOL BEAVRS Cycle 1: power history 23 1 st KIT-SJTU Student Workshop
SERPENT2/SCF Validation MIT BEAVRS benchmark HZP physics test HP measurements at 18 days (693 MWth) after BOL Location: B03 Location: B13 PhD: M. Däubler M. Daeubler, L. Mercatali, V. Sanchez, R. Stieglitz und R. Macian-Juan, Validation of the Serpent 2-DYNSUB code sequence using the Special Power Excursion Reactor Test III (SPERT III), p. Submittet to ANE for publication, 2015. 24 1 st KIT-SJTU Student Workshop
Final Conclusions and Outlook Conclusions: Numerical simulation tools for safety evaluations undergo continuous developments and must correspond to the state-of-the-art Need to move towards the increase of the spatial and energy resolution is recognized Advances in computer power paves the ways for high fidelity simulations and full use of big HPC clusters now available Outlook: New powerful full transport solvers based on PN, SN and MOC are under development e.g. SCOPE2, ntracer, MPACT Development of dynamic Monte Carlo codes (prompt and delayed neutrons, control rod movements) strong competitors of classical deterministic codes safety-related applications (long term) EU H2020 McSAFE Project (KIT Coordinator): 2017-2020 25 1 st KIT-SJTU Student Workshop
Outlook: Dynamic MC/TH: REA Analysis (PWR 3x3 Minicore) MOX FA UOX FA REA Scenario: HZP Ejection of CR within 0.1 s Bart L. Sjenitzer, J. Eduard Hoogenboom, Javier Jiménez Escalante, Victor Sanchez Espinoza; Coupling of dynamic Monte Carlo with thermal-hydraulic feedback. ANE 76 (2015)27-39. Power evolution: comparison of MC/TH and NodalDiffusion/TH Codes Minicore: 3x3 FA (UOX/MOX) 26 1 st KIT-SJTU Student Workshop
McSAFE: High Performance Monte Carlo Methods for SAFEty Demonstration EU H2020 McSAFE (2017-2020): coordinated by V. Sanchez (KIT) 27 1 st KIT-SJTU Student Workshop
For papers, see HPMC site: http://www.fp7-hpmc.eu/ Miriam Knebel, Luigi Mercatal, Victor Sanchez, Robert Stieglitz, Rafael Macian-Juan; Validation of the Serpent 2-DYNSUB code sequence using the Special Power Excursion Reactor Test III (SPERT III). Annals of Nuclear Energy 91 (2016) 79-91 L. Mercatali, A. Venturini, M. Daeubler, V.H. Sanchez; SCALE and SERPENT solutions of the OECD VVER-1000 LEU and MOX burnup computational benchmark. Annals of Nuclear Energy 83 (2015) 328 341 Däubler M., Ivanov A., Sjenitzer B., Sanchez V., Stieglitz R., Macian-Juan R.; High-Fidelity coupled Monte Carlo Neutron transport and thermalhydraulic simulations using Serpent 2/SUBCHANFLOW - Part I: Implementation and Solution Verification. Annals of Nuclear Energy 83 (2015) 352 375 Bart L. Sjenitzer, J. Eduard Hoogenboom, Javier Jiménez Escalante, Victor Sanchez Espinoza; Coupling of dynamic Monte Carlo with thermalhydraulic feedback. ANE 76 (2015)27-39. Miriam Daeubler, Nico Trost, Javier Jimenez, Victor Sanchez, Robert Stieglitz, Rafael Macian-Juan; Static and transient pin-by-pin simulations of a full PWR core with the extended coupled code system DYNSUB. Annals of Nuclear Energy 84 (2015) 31 44 Ivanov, V. Sanchez, R. Stieglitz, K. Ivanov; Large-scale Monte Carlo neutron transport calculations with thermal hydraulic feedback. Annals of Nuclear Energy 84 (2015) 204 219 Ivanov, V. Sanchez, R. Stieglitz, K. Ivanov; Internal multi-scale multi-physics coupled system for high fidelity simulation of light water reactors, Annals of Nuclear Energy, 66C (2014) p.104-112. A. Ivanov, V. Sanchez and R. Stieglitz, K. Ivanov; High Fidelity Simulation of Conventional and Innovative LWR with the Coupled MONTE-CARLO Thermal Hydraulic System MCNP-SUBCHANFLOW. Nuclear Engineering and Design 262 (2013) 264-275. Ivanov and V. Sanchez; VARIANCE REDUCTION IN HIGH RESOLUTION COUPLED MONTE CARLO - THERMAL-HYDRAULICS CALCULATIONS. MC2015 P304. Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo (MC) Method, Nashville, Tennessee. April 19 23, 2015, (invited). V. Sanchez and A. Ivanov, J.E. Hoogenboom; TOWARDS THE DEVELOPMENT OF COUPLED MONTE CARLO /SUBCHANNEL THERMAL HYDRAULIC CODES FOR HIGH-FIDELITY SIMULATION OF LWR FULL CORES. MC2015 P134. Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo (MC) Method, Nashville, Tennessee. April 19 23, 2015, (invited). J. Eduard Hoogenboom, Aleksandar Ivanov and Victor Sanchez; MAXIMUM EFFICIENCY IN MASSIVELY PARALLEL EXECUTION OF MONTE CARLO CRITICALITY CALCULATIONS; MC2015 P139. Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo (MC) Method, Nashville, Tennessee. April 19 23, 2015. 28 1 st KIT-SJTU Student Workshop